Solid Formulation of Trichoderma virens for the Management of Banana Anthracnose Caused by Colletotrichum musae

Abstract

Trichoderma spp. widely used as biocontrol agents for controllin g a wide range of plant diseases. Banana anthracnose caused by Colletotrichum musae is a prominent, widely distributed postharvest disease. This study was carried ou t to assess the effectiveness of locally isolated Trichoderma virens against C. musae and the mass producti on of T. virens using locally available, low-cost solid substrates. T. virens was tested for the inhibition of C. musae isolate in -vitro and in-vivo by dual plating and inoculating into two varieties of ripened banana: Kolikuttu and Cavendish, respectively. For mass production, T. virens was inoculated into different solid substrates including scraped coconut  waste, sawdust, tea waste, seeds from rice, finger millet, and maize, dried pieces of water hyacinth plant, paddy straw, and Panicum maximum leaves; regularly taken spore co unts (cfu/g) and checked for viability by plating after 12 weeks of storage. The pathogen inhibition percentag e by T. virens was 74.10%. Disease severity was 0% in Kolikuttu and 19% in Cavendish after 5 days of T. virens spore appli cation (1x107 spores/ml). Significantly higher (p≤0.05) mean spore production resulted in rice seeds (9.345x109 spores/g) compared to the other substrates and the least resulted in sawdust (1.808x109 spores/g) at the 8th week after  T. virens inoculation. Spores of T. virens were viable in all the tested substrates throughout the study period. The results conclude that T. virens is capable of controlling banana anthracnose and can be efficiently mass-produced by using rice seeds, dried pieces of P. maximum leaves, and f inger millet seeds as substrates.